Since the industrial revolution, society has been reliant on fossil fuels as its foremost energy source. It is common knowledge that fossil fuels are in limited supply and that the combustion of fossil fuels releases environmental pollutants (e.g., carbon monoxide). Petroleum, which currently supplies approximately 40% of the planet's energy, has overtaken coal as the most commonly consumed fossil fuel. One of petroleum's major uses is the production of gasoline, which drives the internal combustion engines of the more than 530 million gasoline-powered cars currently in use throughout the world. In contrast, a much smaller number of automobiles in existence today utilize alternative fuels.
Hybrid electric vehicles improve gas mileage by combining a battery-powered electric motor/generator with a highly efficient heat engine, typically an internal combustion engine. In some of these hybrid or mild-hybrid power train systems, an electric motor-generator system replaces the conventional starter motor and the alternator. When the hybrid vehicle is decelerating or is stopped, the fuel flow to the gasoline-powered engine is shut-off to improve fuel economy. The motor-generator system of the hybrid vehicle is implemented to enable this fuel shut-off feature with substantially no effect on drivability.
Owners of hybrid automobiles have expressed a desire that they be provided with data regarding short term and long term fuel savings. Considering this, it should be appreciated that it would be desirable to provide a fuel usage and savings informational system for use on an alternative fuel vehicle that determines the vehicle's fuel consumption and compares it to the quantity of fuel that would be consumed by an analogous, exclusively gasoline-powered vehicle under similar driving conditions. It should further be appreciated that it would be desirable for such a fuel informational system to provide accurate data regarding the vehicle's instantaneous fuel usage that a driver may utilize to learn how to operate the vehicle in a more fuel efficient manner. Furthermore, other desirable features and functions of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.